External shot blasting line
The bare pipes are received at the incoming racks and are then pre-heated and shot- blasted to specific surface profiles.
As each pipe is shot blasted, the blasted profile and depth of anchor pattern is tested to ensure quality.
Pipes which are rejected after shot blasting are re worked and shot blasted again before transferred to coating line.

External coating line
The shot blasted pipes are acid washed and chromate treated before entering the induction heater/Gas Furnace where thePipe is heated to a temperature recommended by the epoxy manufactures.
Epoxy powder is sprayed onto the pipes in the Epoxy Booth.
If three layer coating is required co extruded layers of Co Polymer Adhesive and Polyethylene/Polypropylene are wrapped on the pipe surface.
The pipes are subsequently cooled at the Quench station and 100% inspected for holiday. Before final inspection coating is removed from the pipe ends according to specifications.
Final Inspection and marking of coated pipes are carried out as required.

Internal shot blasting line
At the internal shot blasting station bare pipes are shot blasted to achieve desired surface profile.
Grits/shots in the pipes are then cleaned through tilting or by blowing air through the pipe.

Inernal coating line
Internally shot blasted Pipes are transferred to the Coating line.
Epoxy Paint is pre heated to the temperature recommended by epoxy suppliers.
The coating is applied through an automatic airless spray machine to attain the uniform coating thickness.
Once coating is completed the pipe is left for curing and is later 100% inspected for holiday.
Final inspection of internally coated pipe is carried out.

Tags: Coating